To prepare a shaft stub to anchor a bayonet coupling to it, it has been required up to now to provide the shaft stub with a circular groove and to machine the stub end projecting therebeyond with circumferentially spaced openings to be able to push on the rotatable portion of the bayonet coupling, the bayonet ring, up to the circular groove.
By rotation of the bayonet ring, the ring member on the shaft stubs is axially clamped and/or is braced against an abutment.
When, however, shaft stubs are used which only have one circular groove and whose stub end projecting beyond the groove is a closed collar, it is required to machine the circumferentially divided openings in this closed collar.
This machining operation is, for example, required for the shaft stub used in a journal bearing assembly with a hydraulic bearing extractor according to U.S. Pat. No. 3,627,388 in which a circular groove at the end of the shaft stub receives a divided clamping ring. If a shaft stub bearing with a bayonet coupling instead of the divided clamping ring is desired, the roll must be subjected to the costly machining operation at the shaft stub end as described.